The field of the invention is that of assembling optical sources such as VCSEL arrays to substrates containing transmissions links and optical routing members.
As high volume digital systems expand their use of optical interconnects, the need for a manufacturable optical connection system increases.
High volume systems typically have a backplane connecting a number of system boards. Such systems contain arrays of optical sources such as VCSELs that generate light that is modulated to carry data and directed to various locations where detectors such as photodiodes convert the modulated optical radiation to electronic signals that can be processed in conventional digital processing systems.
A recurring problem in the field is that of misalignment in optical connector systems. Signal loss that increases the noise level or renders the signal undetectable occurs frequently. Precision alignment systems require expensive setup and constant maintenance.
The art would benefit from passive alignment systems employing self-aligning structures fabricated at low cost with lithographic precision.
The invention relates to an alignment system for assembling an array of optical sources in alignment with a set of optical transmission members on a system board.
A feature of the invention is the fabrication on the optical chip containing an array of optical sources of passive alignment features.
A feature of the invention is the provision of a simple unit containing an array of lenses in alignment with the array of sources and positioned with alignment members interlocking with the passive alignment features on the optical chip.
Another feature of the invention is the provision of a replaceable optical switching structure fitting into a receptacle matched to the array of lenses, for receiving radiation from the VCSEL array and directing it to various locations on the system board.
Another feature of the invention is a structure for mounting a logic chip and an optical chip on a chip carrier, with the optical chip being mounted on the side of the carrier facing the system board on which the carrier is mounted, so that radiation travels in a straight path from optical sources on the optical chip into optical transmission guides on the board.